In a wireless communications system, there is a random access resource to be used by a terminal (user equipment (UE)) during random access to a network when an emergent uplink service occurs. A process in which the UE establishes a connection to the network is referred to as a random access process.
Currently, in most systems, a random access resource is configured by using a system broadcast. However, once the random access resource is configured by using the system broadcast, if a configuration needs to be changed, a change can be made within only a change period. As a result, such a change takes place relatively slow. Such a configuration method is a practically “semi-static” configuration method. Moreover, once a configuration using a system broadcast is changed, all UEs need to be notified, resulting in a very high cost. Therefore, in some machine-to-machine (M2M) communications systems, if an emergency such as afire or an earthquake occurs and a network needs to rapidly change a configuration of a random access resource, network congestion occurs easily. If excessive uplink resources are configured for random access, within a fairly long period of time, these resources cannot be used by UE to send uplink data, causing a great waste of resources.
Therefore, how to flexibly configure a random access resource becomes a technical problem that needs an urgent solution.